Diffusion transfer color products and processes simultaneously utilizing exposed and unexposed silver halides

ABSTRACT

PHOTOGRAPHIC SYSTEMS FOR PREPARING COLOR TRANSFER IMAGES EMPLOYING A PHOTOSENSITIVE ELEMENT HAVING AT LEAST ONE LIGHT-SENSITIVE SILVER HOLDS EMULSION HAVING ASSOCIATED THEREAFTER A FIRST COLOR-PROVIDING MATERIAL WHICH A NORMALLY DIFFUSIBLE IN AN AQUEOUS ALKALINE PROCESSING MEDIUM AND A SECOND COLOR-PROVIDING MATERIAL WHICH IS NOT, WHEREIN THE PHOTOSENSITIVE ELEMENT IN EXPOSED AND THEREAFTER DEVELOPED, AS A FUNCTION OF DEVELOPMENT THE FIRST-NAMED MATERIAL IS SELECTIVELY IMMOBILIZED TO PROVIDE A FIRST IMAGEWISE DISTRIBUTION OF MOBILE AND DIFFUSIBLE COLOR-PROVIDING MATERIAL AND SAID SECOND-NAMED MATERIAL IS SELECTIVELY RENDERED DIFFUSIBLE TO PROVIDE A SECOND IMAGEWISE DISTRIBUTION OF MOBILE AND DIFFUSIBLE COLORPROVIDING MATERIAL IN AREAS CORRESPONDING TO SAID FIRST IMAGEWISE DISTRIBUTION, AND SAID TWO IMAGEWISE DISTRIBUTIONS OF MOBILE AND DIFFUSIBLE COLOR-PROVIDING MATERIAL ARE THEN TRANSFERRED TO A DYEABLE STRATUM TO IMPART THERETO A COLOR TRANSFER IMAGE. THE PHOTOGRAPHIC SYSTEMS ARE ALSO CHARACTERIZED AS EMPLOYING EXPOSED SILVER HALIDE TO CONTROL TRANSFER OF ONE COLOR-PROVIDING MATERIAL; AND UNEXPOSED SILVER HALIDE TO CONTROL TRANSFER OF THE OTHER.

June 15, 1971 R. K. STEPHENS 3,585,

DIFFUSION TRANSFER COLOR PRODUCTS AND PROCESSES SIMULTANEOUSLY vUTILIZING EXPOSED AND UNEXPOSED SILVER HALIDES Filed May 9, 1969 gSUPPORT SILVER HALIDE EMULSION PROCESSING COMPOSITION IMAGE-RECEIVINGLAYER -SUPPORT 7A 5 su P PO R T 'NOND|FFUS|BLE DYE+ NUCLEATING AGENT DYEDEVELOPER --s|LvER HALIDE EMULSION 3O lsup oRT 32 }'DIFFUSIBLE DYE 34*""SPACER LAYER 3e NON-DIFFUSIBLE DYE 38 I my |-S|LVER HALIDE EMULSIONINVISNTOR. ROBERT K. STEPHENS U Gal 4A5, yd/10.66 ATTORNEYS UnitedStates Patent O U-S. Cl 963 25 Claims ABSTRACT OF THE DISCLOSUREPhotographic systems for preparing color transfer images employing aphotosensitive element having at least one light-sensitive silver halideemulsion having associated therewith a first color-providing materialwhich is normally diffusible in an aqueous alkaline processing mediumand a second color-providing material which is not, wherein thephotosensitive element is exposed and thereafter developed, as afunction of development the first-named material is selectivelyimmobilized to provide a first imagewise distribution of mobile anddiffusible color-providing material and said second-named material isselectively rendered diffusible to provide a second imagewisedistribution of mobile and diifusible colorproviding material in areascorresponding to said first imagewise distribution, and said twoimagewise distributions of mobile and ditfusible color-providingmaterial are then transferred to a dyeable stratum to impart thereto acolor transfer image. The photographic systems are also characterized asemploying exposed silver halide to control transfer of onecolor-providing material; and unexposed silver halide to controltransfer of the other.

BACKGROUND OF THE INVENTION US. Pat. No. 2,983,606 issued to Howard G.Rogers discloses processes for forming color transfer images utilizingdye developers (dyes which are also silver halide developing agents). Insuch systems, a photosensitive element containing at least onelight-sensitive silver halide emulsion and associated dye developer isexposed to form a developable image; the thus exposed element is thencontacted with an aqueous alkaline processing composition to develop theimage and, as a function of development, to form an imagewisedistribution of mobile and diffusible dye developer; and this imagewisedistribution is then transferred, at least in part, to a superposeddyeable stratum to impart thereto a color transfer image. Multicolorimages may be obtained by having two or more emulsion layers andassociated dye developers. Accurate color reproductions may be obtainedby providing a blue-sensitive, a green-sensitive and a red-sensitivesilver halide emulsion layer, the emulsion layers having associatedtherewith a yellow, a magenta and a cyan dye developer, respectively.Multilayer photosensitive elements of this nature are described withmore particularity in US. Pat. No. 3,345,163 issued to Edwin H. Land andHoward G. Rogers.

The copending application of Stanley M. Bloom, Ser. No. 655,338 filedJuly 24, 1967, describes and claims novel compounds containing acolor-providing moiety and an anchoring or immobilizing moiety. Thesecompounds are immobile and non-diffusible in an aqueous alkaline medium,but are capable of providing, upon oxidation, an oxidation product whichmay auto-react intramolecularly to form a heterocyclic ring and, as afunction of this ring formation, to split off a mobile and diifusiblecolor-providing material. This reaction may also be defined as aring-closure of the oxidation product resulting "ice in a separation orfreeing of the mobile color-providing moiety from the anchoring moiety.

The copending application of Stanley M. Bloom and Howard G. Rogers, Ser.No. 655,440 filed July 24, 1967 now US. Pat. 3,443,940, disclosesvarious photographic systems employing compounds such as those describedand claimed in the aforementioned application Ser. No. 655,338 to obtaincolor transfer images. In one of the disclosed systems, a photosensitiveelement containing at least one light-sensitive silver halide emulsionand associated immobile compound such as described above is exposed toprovide a developable image; the thus exposed element is contacted withan aqueous alkaline processing composition including a silver halidedeveloping agent and a silver halide solvent to develop the image and toform an imagewise distribution of a soluble silver complex in terms ofundeveloped areas of the emulsion according to principles well known insilver diffusion transfer; the resulting soluble silver complex is thentransferred to contact the color-providing material, whereby thecolorproviding material reduces the silver complex and is in turnoxidized to provide an oxidation product which then autoreactsintramolecularly to effect ring-closure and to split off the mobile anddilfusible color-providing moiety to provide in turn an imagewisedistribution of mobile and diffusible color-providing material in termsof unexposed areas of the emulsion; and this imagewise distribution isthen transferred, at least in part, by imbibition, to a superposeddyeable stratum to impart thereto a positive color transfer image.

The copending application of Stanley M. Bloom and Robert K. Stephens,Ser. No. 655,436, filed July 24, 1967 now US. Patent 3,443,939,disclosed systems employing the aforementioned non-diffusible compoundsto obtain negative color transfer images. According to this copendingpatent application a photosensitive element containing at least onelight-sensitive silver halide emulsion and associated compound of theforegoing description is exposed and then developed with an aqueousalkaline processing composition including a silver halide developingagent which upon development provides an oxidation product capable ofbeing reduced by a redox reaction with the aforementioned compound, thedeveloper further being sufficiently mobile in its oxidized state so asto be capable of migrating to the layer containing the color-providingcompound; oxidizing the developing agent as a function of development toprovide an imagewise distribution of oxidized developing agent in termsof exposed and developed areas of the emulsion; transferring thisimagewise distribution at least in part, to contact the colorprovidingcompound, whereby a redox reaction takes place to reduce the developingagent and to oxidize the color providing compound to form an oxidationproduct which then ring-closes to split off the mobile color-providingmoiety in turn to form an imagewise distribution of mobile anddilfusible color-providing compound in terms of exposed areas of theemulsion; and transferring this latter imagewise distribution, at leastin part, by imbibition to a superposed dyeable stratum to impart theretoa negative color transfer image.

The copending application of Howard G. Rogers, Ser. No. 655,502 filedJuly 24, 1967 now US. Patent 3,443,941, disclosed various systems forforming color transfer images utilizing silver ions to control colortransfer. One of the disclosed systems utilizes silver ions toimmobilize a colorproviding material which is normally mobile anddilfusible in an aqueous alkaline medium. In such a system, aphotosensitive element containing at least one light-sensitive silverhalide emulsion and associated color-providing material is exposed toform a developable image and then developed by applying a processingcomposition including a silver halide solvent. In known manner, animagewise distribution of soluble silver complex is formed in terms ofunexposed areas of the emulsion. This imagewise distribution istransferred to the color-providing material where it immobilizes thecolor-providing material in terms of unexposed areas of the emulsion,thereby providing an imagewise distribution of mobile and dilfusiblecolorproviding material in terms of exposed areas. This latter imagewisedistribution is then transferred, at least in part, by imbibition, to asuperposed strata to impart thereto a negative color transfer image.

The present invention utilizes the principles of the inventionsdescribed and claimed in the aforementioned patent and copendingapplications in a novel manner to form color transfer images.

SUMMARY OF THE INVENTION According to the present invention, diffusiontransfer systems for preparing color images are provided employingphotosensitive elements comprising at least one light-sensitive silverhalide emulsion having associated therewith a color-providing materialnormally ditfusible in an aqueous alkaline medium and a color-providingmaterial normally non-diffusible in an aqueous alkaline medium. Reactionmechanisms are employed to form, as a function of development, animagewise distribution of color-providing ingredients containing each ofthese color-providing materials, which is then transferred to asuperposed stratum to form a color transfer image.

In one embodiment of this invention, a dye developer is employed as thenormally dilfusible color-providing material and a compound containing acolor-providing moiety and an anchoring moiety, e.g., a compound asdescribed in the aforementioned application Ser. No. 655,338, isemployed as the non-dilfusible color-providing material.

In this embodiment of the invention, as a function of development, dyedeveloper is oxidized and immobilized for transfer in terms of exposedareas of the light-sensitive emulsion to provide an imagewisedistribution of unoxidized and diffusible dye developer in terms ofunexposed areas; and at substantially the same time a soluble silvercomplex formed in terms of unexposed areas is employed to release thediffusible dye moiety from the anchoring moiety of the normallynon-diffusible compound, thereby forming a second imagewise distributionof color-providing material in terms of unexposed areas of the emulsion.Both of these imagewise distributions are then transferred to asuperposed stratum to impart thereto a positive color transfer image.

In a second embodiment of the invention, a compound of the typedescribed above in connection with the aforementioned U.S. Patent3,443,941 is employed as the normally dilfusible color-providingmaterial and one of the aforementioned non-diffusible compoundscontaining a diffusible color-providing moiety and an anchoring moietyis employed as the non-diffusible compound. In this embodiment, animagewise distribution of the former is obtained according to theprocedures described in the aforementioned U.S. Patent 3,443,941; and animagewise distribution of the latter is obtained by the redox reactiondescribed in the aforementioned U.S. Patent 3,443,939. These twoimagewise distributions are then transferred to a superposed stratum, byimbibition, to form a negative color transfer image.

The present invention may be said to be predicated upon the use ofnegative silver, i.e., exposed silver in the photosensitive element, tocontrol transfer of one color-providing material, and positive silver,i.e., unexposed silver in the form of a soluble silver complex, tocontrol transfer of another color-providing material to from a colortransfer image in terms of both; as distinguished from prior colortransfer processes which utilize either negative or positive silver, butnot both, to form color transfer images. The ability to employ bothnegative and positive silver in two non-competing reaction mechanisms tocontrol dye transfer provides certain significant advantages,

some of which should be apparent and others which will be discussed withparticularity hereinafter.

DESCRIPTION OF DRAWING FIG. 1 is a partially schematic, enlarged,fragmentary, sectional view illustrating one previously exposedphotographic product of this invention during processing thereof;

FIG. 2 is a partially schematic, enlarged, fragmentary, sectional viewof another photographic product of this invention; and

FIG. 3 is a similar view of yet another photographic product of thisinvention.

As was indicated previously, this invention relates to photography andmore particularly to novel products and processes for preparing colortransfer images.

A primary object of this invention therefore is to provide novelproducts and processes for preparing monochromatic or multicolortransfer images.

Another object is to provide novel color diffusion transfer systemswherein two different reaction mechanisms are employed substantiallysimultaneously to provide, as a function of development, two imagewisedistributions of color-providing material available for transfer to asuperposed stratum to impart thereto a color transfer image.

Still another object is to provide novel color diffusion transfersystems employing at least one color-providing material normallydilfusible in an aqueous alkaline processing medium and at least onecolor-providing material normally non-diffusible in an aqueous alkalineprocessing medium.

A still further object is to provide novel products and processes of theforegoing description.

Yet another object is to provide novel color transfer systems whereinboth exposed and unexposed silver halide are employed to controltransfer of color-providing materials.

Other objects of the invention will in part be obvious and will in partappear hereinafter.

The invention accordingly comprises the several steps and the relationand order of one or more of such steps with respect to each of theothers, and the product possessing the features, properties and therelation of elements which are exemplified in the following detaileddisclosure, and the scope of the application of which will be indicatedin the claims.

For a fuller understanding of the nature and objects of the invention,reference should be had to the following detailed description taken inconnection with the accompanying drawing.

Color transfer processes are known which use unexposed silver halide tocontrol the transfer of color-providing material to a superposed stratumto form a color transfer image. Color transfer processes are also knownwhich use exposed silver halide to control the transfer ofcolor-providing material to a superposed stratum. The photographicsystems described and claimed in the aforementioned U.S. Pats. 3,443,941and 3,443,939 are examples of the former; and the systems described andclaimed in the aforementioned U.S. Pat. No. 2,983,606 are examples ofthe latter.

The essence of the present invention is providing a system whichcombines the two so that the color transfer image is formed in terms ofat least two color-providing materials, one being a color-providingmaterial whose transfer is controlled by unexposed silver halide; theother being a color-providing material whose transfer is controlled byexposed silver halide. These color-providing materials may be completedyes or they may be couplers or dye intermediates, i.e., materials whichform complete dyes at some time during or after transfer. Because of theready availability of suitable complete dyes, these materials arepreferred to dye intermediates which require a subsequent action, e.g.,a coupling reaction, to provide the desired color image. In any eventthe two color-providing materials may possess substantially the samespectral absorption characteristics, for example, they both may beyellow, magenta or cyan dyes, or they may be of entirely differentcolors. In the former case, the resulting color transfer image would beof substantially the same color as either of the color-providingmaterials alone; whereas in the latter case, the color of the resultingimage would be entirely different, being a product of the sum total ofthe two. Thus, for example, if the two color-providing materials arecomplementary in color, and substantially equivalent amounts in terms ofcovering power or density are transferred, the resulting image would beessentially neutral in color, i.e., black or a shade of black.

Common to all of the systems contemplated by this invention is the useof a photosensitive element having at least one light-sensitive silverhalide emulsion having associated therewith a normally ditfusiblecolor-providing material and a normally non-ditfusible color-providingmaterial; and an aqueous alkaline processing composition including asilver halide solvent.

As used herein and in the appended claims, the term diflusible refers tothe property of the color-providing material of being mobile andtransferable in the aqueous alkaline processing medium from the layer inwhich it is initially contained to a superposed stratum duringprocessing. The term non-difiusible therefore refers to the converseproperty.

In one aspect of this invention, use is made of a dye developer, i.e., adye which is also a silver halide developing agent, as the normallydilfusible color-providing material; and a compound containing adiifusible color-providing moiety and an anchoring moiety rendering thecompound non-difiusible as the non-diffusible color-providing material.

Dye developers are per se well known in the art and suitable dyedevelopers of various structures and colors :are disclosed, for example,in US. Pat. No. 2,983,606, in various patents cited therein, and in manyother patents, as well. In general, a dye developer is a compoundcontaining a dye moiety and a silver halide developing function linkedto the dye moiety through a covalent bond or a divalent organic linkinggroup. As is well known, the developing function generally is a benzenenucleus containing amino and/ or hydroxy groups in either the ortho orpara positions. Dihydroxyphenyl substituents such as hydroquinonyl andsubstituted derivatives thereof are generally preferred. The dye moietymay comprise any chromophoric system contributing the desired chemicaland physical characteristics. Included are azo, anthraquinone,azomethine, phthalocyanine dyes, etc. The dye developer may, if desired,be in the form of a metal complex, e.g., a chromium-complexed dyedeveloper.

As was mentioned previously, useful compounds containing a diffusiblecolor-providing moiety and an anchoring moiety rendering the compoundnon-dilfusible include those described and claimed in copendingapplication Ser. No. 655,338 and which may be represented by theformula:

wherein:

A and 'A each represent the atoms necessary to complete a benzene ornaphthalene ring, which ring may be further substituted;

D is a color-providing moiety, e.g., a complete dye such as a monoazo,disazo or anthraquinone dye which may, if desired, be metallized inknown manner;

Y is any substituent which completes or forms an amide with, and reducesthe basic character of the amino group in the 3-position, such as theresidue of an acid, linking the color-providing moiety D to the3-nitrogen atom, and which is capable of being eliminated during thering formation to be described with more particularity hereinafter,e.g.,

l 0 lower alkyl etc.;

R and R each represent an anchoring or immobilizing substituentrendering the compound non-diffusible, e.g., higher alkyl such as decyl,dodecyl, stearyl, oleyl, etc. linked directly to the aromatic nucleus orlinked indirectly thereto through an appropriate linking group,

OONH-, Q-oonmetc., an aromatic ring, e.g., of the benzene or naphthaleneseries, or a heterocyclic ring, which rings may be either bonded to asingle carbon atom of the aromatic nucleus or fused thereto, i.e.,bonded to a pair of adjacent carbon atoms; or R and/ or R may be aplurality of short chain radicals which together provide the anchoringmoiety, each of said short chain radicals being linked directly orindirectly to a different carbon atom of the aromatic nucleus formed bythe A and/or A moieties;

. X is hydrogen, hydroxy, amino, e.g., a primary, secondary or tertiaryamino substituent of the formula:

wherein each R may be hydrogen, a hydrocarbon radical, e.g., alkyl, suchas methyl, ethyl, butyl, dodecyl, etc., aryl such as phenyl or naphthylattached through a carbon atom thereof to the nitrogen atom, a cyclicalkyl such as cyclopentyl or cyclohexyl, i.e., where both R s arealkylene comprising together with the nitrogen atom a heterocyclic ring,a substituted alkyl, such as hydroxyethyl, methoxyethoxyethyl,polyglycoloxyethyl, carboxymethyl, benzyl, phcnylethyl,sulfo-phenylethyl, acetylamino-phenylethyl, succinylamino-phenylethyl,furanemethyl, etc.; or a substituted aryl such as methylphenyl,ethylphenyl, etc., or the anchoring substituent R;

X is hydrogen, hydroxy, an amino group such as may be contained by saidX moiety, as previously described, or the anchoring substituent Rprovided that one of said X and X moieties must be hydroxy or amino;

R is hydrogen, an alkyl such as methyl, ethyl, propyl, butyl, hexyl,octyl, dodecyl, cyclohexyl, etc.; or a substituted alkyl such as2-hydroxyethyl, 3-dihydroxypropyl, carboxymethyl, carboxyethyl,carboxybutyl, carboxydecyl, hydroxyethyl-ether, polyglycoloxyethyl,furanemethyl, benzyl, phcnylethyl, carboxyphenylethyl,sulfo-phenylethyl, acylaminophenylethyl, etc.; and

n and n each is a positive integer from 1 to 2, provided that when R orR alone or together comprise one of those heretofore named substituentsrendering the compound non-ditfusible, either or both of n and n may be1 but when R and R alone or together do not provide such an anchoringmoiety at least one of n and n must be 2.

Preferred'are those compounds within the scope of the above formulawhich are of the following formula:

ROM)

CH O- COOCgHs SOaH ll @CIhOIhC-NH-C llu NH @NHSOz-N=N H0 HITISOz-GCH:

S OzNH Ohm! SO NH m I I NH -C 7H 5 0 CH3 In the embodimentof theinvention using the combination of a dye developer and a non-dilfusiblecolor-providing material of the foregoing description, a photosensitiveelement including at least one light-sensitive silver halide emulsion isfirst exposed to form a developable image. This image is then developedby contacting it with an aqueous alkaline processing compositionincluding a dye developer and a silver halide solvent to develop theimage. In known manner, exposed silver halide controls the diifusibilityof the dye developer by being reduced and as a function of thisdevelopment causing the dye developer to in turn be oxidized to providean oxidation product which is less mobile and ditfusible than theunoxidized dye developer present in terms of unexposed and undevelopedareas of the emulsion. The dye developer is preferably containedinitially in a layer associated with the silver halide emulsion, the dyedeveloper solution being obtained by contacting the photosensitiveelement with the aqueous alkaline medium. However, in monochromaticprocesses, the dye developer may be contained initially in theprocessing composition in the manner known in the art.

In either event, at substantially the same time as the exposed silverhalide is developed to provide an imagewise distribution of diifusibledye developer in terms of unexposed areas of the emulsion, an imagewisedistribution of soluble silver complex is formed in terms of unexposedand undeveloped silver halide, according to principles well known insilver diifusion transfer photography. This imagewise distribution ofsoluble silver complex migrates or is transferred in the processingcomposition to a layer associated with the silver halide emulsion,containing the non-ditfusible color-providing material where the tworeact to reduce the silver complex and as a function thereof to oxidizethe colorproviding material. In the manner described with particularityin the aforementioned copending application Ser. No. 655,440, anoxidation product of this colorproviding material is formed which thenring-closes intramolecularly and splits off the diffusiblecolor-providing moiety, thereby providing an imagewise distribution ofthis difiusible color-providing moiety in terms of unexposed areas ofthe emulsion. It will thus be seen that the foregoing reactionmechanisms provide two imagewise diffusible distributions which arevirtually identical in terms of the point-to-point degree of exposure ofthe silver halide emulsion. These two imagewise distributions are thentransferred, by imbibition, to a superposed layer to impart thereto acolor image in terms of the two.

This aspect of the invention is illustrated in FIGS. 1 and 2. FIG. 1shows an exposed photosensitive element of this aspect of the inventionduring development. The photo-sensitive element comprises a suitableopaque or transparent support containing a layer 12 of nondiffusible dyeand a nucleating agent; layer 14 of the dye developer; and silver halideemulsion layer 16. At some time during or after exposure, processingcomposition 18 is spread between the thus exposed photosensitive elementand a superposed image-receiving element comprising an image-receivinglayer or dyeable stratum 20 contained on a suitable support 22. After asuitable processing time, e.g., 60 seconds, the respective elements arethen separated to reveal a positive color image on the image-receivingelement.

Supports 10 and 22 may comprise any of the materials heretofore employedfor such purposes, e.g., a cellulose ester such as cellulose acetate,polyvinyl acetal, polystyrene, polyethylene terephthalate, polyethylene,paper, glass, etc.

Layer 12 comprises the non-diifusible color-providing material andsilver precipitating or physical development nuclei contained in asuitable alkali-permeable matrix, e.g., gelatin. Such nuclei, which arewell known in the art, include noble metals such as silver or gold;colloidal metal sulfides, selenides, and tellurides; metal proteinatessuch as silver proteinates; and such organic sulfur-containing compoundsas thiourea, xanthates, etc. While the precipitating nuclei are shown tobe contained in the same layer, they may be contained in a contiguouslayer, as discussed in the aforementioned US. Patent 3,443,940.

Dye developer layer 14 may, of course, be prepared by any of the methodsheretofore known and described in numerous patents, e.g., by coatingfrom a cellulose acetate hydrogen phthalate, gel or solid dispersions,etc.

Emulsion layer 16 comprises any of the conventional silver halideemulsions, e.g., silver chloride, silver bromide, silver bromoiodide,silver chlorobromide or silver chlorobromoiodide. It may'thus be a highspeed or a low speed emulsion. The emulsion layer may also contain thevarious additives frequently employed in such layers, e.g., opticalsensitizers, antifoggants, hardeners, plasticizers, coating aids,speed-increasing materials, etc. The dispersing agent or substrate forthe silver halide may be gelatin or some other material.

Receiving layer 20 comprises a dyeable stratum generally including amordant. A preferred image-receiving element is one comprising a layerof a 2:1 mixture by weight of polyvinyl alcohol and poly-4-vinylpyridine; a layer of polyvinyl alcohol, and a layer of a half-butylester of poly-(ethylene/maleic anhydride) coated on a baryta papersupport, as disclosed in US. Pat. No. 3,362,- 819 issued to Edwin H.Land.

Processing composition 18 includes at least an aqueous solution of analkaline material such as sodium or potassium hydroxide, and a silverhalide solvent such as sodium or potassium thiosulfate. -It may alsocontain additional reagents performing specific desired functions, e.g.,viscous film-forming reagents such as hydroxyethyl cellulose, sodiumcarboxymethyl cellulose, etc., antifoggants and the like, as Well asaccelerating or auxiliary silver halide developing agents such asp-methylphenylhydroquinone. Any of the aforementioned components of theprocessing composition may, if desired, be present initially in the filmunit, in which case the processing composition providing the desiredingredients is formed by contacting the film unit with the aqueousmedium therefor. As was mentioned previously, in monochromatic systems,the dye developer may also be contained initially in the processingcomposition. In any event, the processing composition may, if desired,be confined in a frangible container or pod such as described, forexample, in US. 2,543,181 and 2,634,- 886, issued to Edwin H. Land.

As was discussed in the aforementioned U.S. Pats. 3,443,940 and3,443,939, in systems employing non-diffusible compounds of theforegoing description two competing reactions are possible: (1) thereaction between the soluble silver complex and the color-providingmaterial; and (2.) a redox reaction between the color-providing materialand oxidized silver halide developing agent, i.e., developing agentoxidized as a function of development of exposed silver halide. It ispossible for both reactions to occur at the same time so that a uniformtransfer of the released diffusible color-providing moiety occurs inboth exposed and unexposed areas. In this aspect of the invention itwill, therefore, be apparent that any redox reaction between thenon-diffusible compound and oxidized developer should be avoided. Sincethe oxidized dye developer is not appreciably mobile, in many instancesselection of appropriate dye developers and imbibition times willsuffice. In other instances, it may be desirable to employ appropriatecontrols for optimum efiiciency. It may be entirely satisfactory toemploy a spacer layer of gelatin, cellulose acetate hydrogen phthalateor some other alkali and dye permeable material between layers 12 and 14to restrain migration of oxidized dye developer and/or acceleratingdeveloping agent (if any). Another system described in US. Pat.3,443,940 for obviating the redox reaction is to include in thephotosensitive element a material which will intercept any oxidizeddeveloper and render it innocuous before it can migrate to thecolor-providing material in layer 26, e.g., by reducing the oxidizeddeveloping agent. Suoh materials may be defined as being scavengers foroxidized developer. Suitable scavengers of this nature are described inUS. Pat. 3,443,940 and copending applications of Stanley M. Bloom etal., Ser. Nos. 655,324 and 655,309, both filed July 24, 1967 now US.Pats. 3,482,971 and 3,459,548 respectively.

FIG. 2 illustrates the use of a scavenger of this description, thescavenger being shown to be contained in a layer 24 between the dyedeveloper layer and the layer containing the non-diifusiblecolor-providing material.

In the aforementioned embodiment of this invention f0? preparingpositive images, reference has been made to the presence ofsilver-precipitating nuclei in the same layer or in a layer adjacent tothe non-ditfusible dye. These nuclei are employed to render the solublesilver complex reducible and the color-providing material oxidized. Itwill be appreciated, however, that if the colorproviding material is anon-discriminating silver halide developer, silver precipitating nucleineed not be employed. It should likewise be apparent that the inventionis not restricted to the specific color-providing materials disclosedabove and described and claimed in copending application Ser. No.655,338.

Another embodiment of this invention employs nonditfusiblecolor-providing materials such as mentioned above and normallydifiFusible color-providing materials (6) OH reactable with silver ionsto be rendered non-diffusible to l form negative color transfer images.In this embodiment, as distinguished from the prior embodiment, exposedsilver halide is employed to control transfer of the nondiffusiblecolor-providing material and unexposed silver halide is employed tocontrol transfer of the diffusible o CH(CH3 2 H color-providingmaterial.

Again, the non-diifusible color-providing material may be one such as isdescribed and claimed in Ser. No. (7) N As examples of diffusible'materials which can be ren- II I dered non-dilfusible by reaction withsilver ions, e.g., a soluble silver complex formed in terms of unexposedN areas of the emulsion, mention may be made of those compoundsdisclosed in US. Pat. 3,443,941 which are I H N I H complete dyescontaining a moiety known in the photo- NH 0 graphic art as an organicantifogging agent. This moiety reacts with silver ions, for example, byforming addition complexes, to provide a relatively stable,non-diffusible silver-containing reaction product. As examples of suchantifoggant moieties, mention may be made of benzimidr 8) =N\ IIIH;azoles, thiocarbazones, benzotriazoles, mercaptothiazoles,hydroxyquinolines, azolethiones, azopyridines, bis-pyra- T zoles,tetrazoindenes, etc. 11

Such compounds may be defined as dyes which are diffusible in an aqueousalkaline medium and which may be represented by the following formula:(9)

l 7 wherein A is a substituent reactable with silver ions to H0 \NJSIIprovide a reaction product which is non-difiusible in an aqueousalkaline medium, e.g., a monovalent radical of an organic antifoggingagent, and D is the remainder of (10) the dye molecule. I

As examples of compounds of this description, mention 2L L may be madeof the following: S

N\ t A Mi i;

l 13 H S l (5) lfHz :CH N .3 1-

(CHM-C0011 I (14) OH N=N "N N 'Cr I l COOH HO N -OH 17 (15 H(|) lTTHzMUNZNIONNZM l l l l 0 s -so 2 l N /N l E 041113 U011; H

O NHCH2CH2- II N/ 1% II N\ 0 r m-01120112 O 18 s 02N- s H N (w) SH HN-on SHLS/ 3 In this embodiment of the invention, exposed silver halidecauses the non-diffusible color-providing material to be oxidized and inturn to ring-close and release the ditfusible color-providing moiety toform an imagewise distribution of the same in terms of exposed areas ofthe emulsion; while the soluble silver complex formed in terms ofunexposed and undeveloped areas migrates or diffuses to the diffusiblecolor-providing moiety to render it non-dilfusible, thereby forming asecond imagewise distribution of this latter diifusible material inareas where it is unreacted with the soluble silver complex. As in thefirst-named embodiment, the two imagewise distributions are thentransferred, by imbibition, to a superposed dyeable stratum to impartthereto a color transfer image. In the latter instance, however, it willbe seen that a negative color transfer image is obtained.

The control of the non-diffusible material by exposed silver halide,i.e., the reaction by which the material is oxidized to provide anoxidation product which autoreacts intramolecularly to ring-close andrelease the diifusi'ble color-providing moiety, is in accordance withthe pro- I8 cedures described in the aforementioned US. Pat. No.3,443,939.

This may be accomplished by a redox reaction with oxidized developingagent obtained by development of the exposed silver halide emulsion witha processing composition containing a silver halide developing agent,the oxidation product of which is mobile and reducible. In such asystem, exposed silver halide is reduced to silver and as a function ofdevelopment the developing agent is in turn oxidized to provide animagewise distribution of oxidized developing agent in terms of exposedareas of the silver halide emulsion. This imagewise distribution ofoxidized developing agent possesses sufficient mobility to migrate andto contact the color-providing material whereby a redox reaction occursin which the developing agent is reduced and the color-providingmaterial is in turn oxidized in an imagewise pattern corresponding toexposed areas of the emulsion to effect ring-closure and subsequentrelease of the mobile color-providing moiety in terms of exposed areasof the emulsion. In the preparation of monochromatic color transferimages by this procedure, the non-diffusible color-providing materialmay be present initially in the photosensitive element or in theprocessing composition.

As examples of silver halide developing agents contemplated by the abovedescription, mention may be made of dihydroxybenzene developers such asthe hydroquinones, aminophenol developers such as metol, diaminobenzenedevelopers such as 2 amino 5 diethylaminotoluene, etc.

As is disclosed in US. Pat. 3,443,939, the non-diffusiblecolor-providing material may also be oxidized in terms of exposed areasof the associated emulsion by a system employing an aqueous alkalineprocessing composition containing no additional silver halide developingagent. In this instance, the color-providing material, which is itself asilver halide developing agent, is the only silver halide developingagent employed. In this system, the nondiflusible color-providingmateriabdeveloping agent associated with the emulsion is contacted withan aqueous alkaline medium to bring it into contact with the exposedemulsion so that exposed silver halide is developed and the material isin turn oxidized. Although the non-diffusible color-providing materialis substantially immobile, i.e., of very low mobility in the processingfluid, since it is of close proximity to the silver halide emulsion,upon a suitable imbibition time, e.g., two minutes, it will migrate toand develop exposed silver halide. It will be noted, however, thatbecause of its relative immobility, longer imbibition times are neededthan in the previously disclosed redox reaction with oxidized developingagent.

The aspect of this invention relating to the formation of negative colortransfer images is illustrated in FIG. 3.

As shown therein, support 30 carries a layer '32 of difiusible dyereactable with silver ions to form a nondiffusible reaction product; alayer 36 of non-diffusible dye capable, upon development of exposedsilver halide, of releasing a diffusible color-providing moiety fortransfer; and a silver halide emulsion layer 38. A spacer layer 34 ispreferably provided between layers 32 and 36.

Support 30 may be of the type described above in connection with FIGS. 1and 2, as may emulsion layer 38 be similar to the emulsion layer ofFIGS. 1 and 2.

Layer 32 comprises a difiusible color-providing material, e. g., anantifoggant dye of the type mentioned above and described in US. Pat.3,443,941, contained in a suitable alkali-permeable matrix of gelatin orthe like.

Spacer layer 34 may be of gelatin, cellulose acetate hydrogen phthalate,etc.

Layer 36 comprises a non-diffusible color-providing moiety such as thosementioned above and described and claimed in Ser. No. 655,338, containedin an alkali-permeable matrix of the type mentioned. It will be notedthat in this embodiment of the invention, unlike that previouslydescribed, layer 36 does not contain any silver-precipitating nuclei. Asdiscussed previously, if it did, the soluble silver complex formed as afunction of development would be reduced and the non-diffusiblecolor-providing material oxidized to release the color-providing moiety,thereby permitting both competing reactions to occur so that a uniformdistribution of material in layer 36 is released for transfer.

To form a negative color transfer image with the photosensitive elementof FIG. 3, the element is exposed and then developed by applying betweenthe thus exposed element and a superposed dyeable stratum an aqueousalkaline processing composition containing at least a silver halidesolvent. In the preferred embodiment, the redox reaction with oxidizeddeveloping agent is employed and the processing composition accordinglycontains a silver halide developing agent of the foregoing descriptionwhich can provide an oxidation product capable of undergoing a redoxreaction with the non-diifusible color-providing material in layer 36.As in the previous embodiment, any of the ingredients of the processingcomposition may be contained initially in the film unit, in which eventthe desired composition is obtained by applying the aqueous mediumtherefor.

Upon applying the processing composition to the exposed element, exposedsilver halide is developed and as a function thereof an imagewisedistribution of diffusible dye moiety is released in terms of exposedareas from the material in layer 36 in accordance with the reactionmechanism previously discussed. At substantially the same time, animagewise distribution of a soluble silver complex is formed in terms ofunexposed areas of the emulsion. This distribution of soluble silvercomplex is transferred through layers 36 and 34 to the diffusiblematerial in layer 32 where, as described above, the diffusible materialis rendered non-diffusible by reaction with the diffusing silvercomplex, thereby leaving remaining in layer 32 an imagewise distributionof diffusible material in areas unreacted with unexposed silver halide.Both of these imagewise distributions of color-providing material arethen transferred, at least in part, by imbibition to a superposeddyeable stratum to impart thereto a negative color transfer image.

It will be appreciated that the elements illustrated in FIGS. 1 through3 are capable of various modifications in structure and in componentsand materials employed without departing from the scope of thisinvention. For example, reference has been made in FIG. 1 to a separateelement containing the image-receiving layer. In lieu thereof, thislayer and the other layers may be contained on a common support. In oneuseful system a layer of a suitable opacifying material may be providedbetween the emulsion layer and the receiving layer. This layer ofopacifying material effectively masks the negative image formed in theemulsion layer and provides the desired background for viewing the colortransfer image formed in or on the receiving layer so that a compositeprint is thereby formed which is viewable without separation of thereceiving layer as a positive color reflection print. As examples ofuseful opacifying materials, mention may be made of pigments,particularly white pig ments such as titanium dioxide, barium sulfate,magnesium oxide, etc.

While for purposes of illustration, the photosensitive elements havebeen shown to contain a single silver halide emulsion and associatedcolor-providing materials, a plurality of such emulsions and associatedmaterials may be employed. Accordingly, both monochromatic andmulticolor transfer images are contemplated by this invention.

The following examples illustrate the practice of this invention.

Example 1 On a cellulose triacetate support was coated a layercontaining, per square foot of surface area, mgms.

of a colloidal silver precipitating agent and 200 mgms. of anon-diffusible reddish dye of the formula:

l IIIII in a gelatin matrix. Over this was applied a spacer layercontaining mgms./ft. of gelatin; a layer contaimng mgms./ft. of a cyandye developer of the formula:

1 \/Q 311 in l OH O After an imbibition period of about 90 seconds, therespect1ve elements were separated to reveal a neutral tone positivecolor transfer image.

Example 2 To prepare a negative color transfer image, one may employ aphotosensitive element such as shown in FIG. 3, using as the diffusiblecolor-providing material a yellow dye of the formula:

and as the non-diffusible color-providing material, a yellow dye of theformula:

Exposure and development may be accomplished as in Example 1, employinga similar developing composition including about 1.6 g. of a suitabledeveloping agent such as metol, to obtain a yellow negative transferimage.

From the foregoing description and illustrative examples, it will beseen that the present invention provides a system wherein twocolor-providing materials are transferred for each silver halideemulsion layer contained in the photosensitive elements, the color ofthe resulting image being a function of the spectral absorptioncharacteristics of the mixture of dyes so transferred, in accordancewith principles well known, for example, in the dye art. If twocomplementary dyes are transferred, e.g., yellow-blue; magenta-green; orcyan-red, a neutral tone image in the black or blue-black family will beobtained. If the two materials providing substantially the same colorare transferred, the resulting image will be likewise of substantiallythe same color. These facts in turn form the basis for certainsignificant advantages provided by this invention.

Regardless of the colors of the materials employed, the presentinvention permits of a more elficient use of silver. In prior processes,image formation is based upon a reaction involving either exposed orunexposed silver halide, so that a given amount of this silver halidemust be present to obtain a color image of a given density. In thepresent invention, use is made of both unexposed and exposed silverhalide so that it is theoretically possible to get the same dye densitywith half as much silver, or, stated another way, twice as much dyetransferred with the same silver. In other words, the present inventionmakes it possible to employ emulsion layers containing less silver,thereby reducing the cost of the product or, conversely, to obtainextremely dense color images with an emulsion containing more or lessstandard amounts of silver. In addition, since both exposed andunexposed silver halide are utilized to control transfer, it is possibleto obtain appreciably higher film speeds.

Where images of a given color are desired, particularly in multicolorsystems for providing reproductions of the highest fidelity and accuracyof color rendition, the present invention provides a novel system forcolor correction. By way of illustration, in multicolor transfersystems, use is customarily made of a blue-sensitive emulsion having ayellow dye associated therewith; a greensensitive emulsion having amagenta dye associated therewith; and a red-sensitive emulsion having acyan dye associated therewith. (Such a system employing dye developershas been previously mentioned.) In these color systems, each of therequisite dyes must ideally combine several features including therequisite color, transferability and stability. It is sometimesdifficult to obtain a single dye possessing all these features to suchan extent in the system employed that a multicolor image of the desiredhigh standards is obtained. It is sometimes the case that a dye that isotherwise acceptable is not quite of the right color. The presentinvention provides a color correction system wherein a second dye may beemployed in association with the emulsion layer, both dyes possessingessentially the same spectral absorption characteristics, but one beingslightly different to correct the color deficiency of the other, so thatthe sum total of dye transferred provides just the right color. Toaccomplish this, substantially equal amounts of each dye may betransferred, or the amounts maybe unequal. For instance, it iscontemplated that one of the two dyes may be present initially inrelatively small amounts where only a slight amount of this dye need betransferred to provide the requisite color.

On the other hand, by providing two complementary dyes, a system isprovided for obtaining dense neutral dye or black-and-white images.Either positive or negative images of this type can be prepared,according to the system employed. It will, therefore, be apparent thatthis embodiment of the invention is not just of interest inblackand-white photography per se, but also in special applications suchas document copying and X-ray. The above-noted efficient use of silvermakes the invention particularly useful in such fields.

Moreover, in certain uses such as X-ray and document copying, a colorimage other than black-and-white is sometimes desirable. It will be seenthat the present invention also permits one to obtain dense monochromesof any color desired.

\It will, therefore, be seen that the present invention provides a colorsystem of use in a variety of different photographic applications.

While reference has been made in the foregoing description andillustrative examples to contain color-providing materials which may beemployed in the practice of this invention, it will be appreciated thatthe invention is not limited thereto. By way of illustration, it iscontemplated that one may employ in the practice of this invention thematerials disclosed, for example, in US. Pats. Nos. 3,227,550,3,227,551, 3,227552, and 3,243,294.

Since certain changes may be made in the above product and processwithout departing from the scope of the invention herein involved, it isintended that all matter contained in the above description or shown inthe accompanying drawing shall be interpreted as illustrative and not ina limiting sense.

What is claimed is:

1. A photographic product comprising a photosensitive element having atleast one light sensitive silver halide layer having associatedtherewith a first color providing material which is normally diifusiblein an aqueous alkaline medium and a second color providing materialwhich is normally non-diffusible in said medium, said dilfusiblematerial being reactable in the presence of an aqueous alkaline mediumwith one or the other of the exposed or non-exposed image patternsformed by exposing the product to a pattern of activating radiation andupon reaction with said pattern providing a non-diffusible reactionproduct; said non-diffusible color providing material being reactable inthe presence of said aqueous alkaline medium with the other remainingsilver halide image pattern to provide an imagewise distribution ofdiffusible dyes whereby said color providing materials form twoimagewise distributions of diffusible dyes which are substantiallyidentical in terms of the point to point degree of exposure of saidsilver halide.

2. A product as defined in claim 1 wherein said diffusiblecolor-providing material is a dye developer.

3. A product as defined in claim 1 wherein said diffusiblecolor-providing material is a dye of the formula:

wherein A is a substituent reactable with silver ions to provide areaction product which is non-ditfusible in an aqueous alkaline medium;and D is the remainder of the dye molecule.

4. A product as defined in claim 1 wherein said nondiffusiblecolor-providing material is a compound containing a diffusiblecolor-providing moiety and an anchoring moiety rendering said compoundnon-diifusible, said compound upon oxidation forming an oxidationproduct which can autoreact intramolecularly to effect ring-closure andto eliminate said diffusible color-providing moiety.

5. A photographic product comprising a photosensitive element having atleast one light-sensitive silver halide layer having associatedtherewith a first color-providing material which is diifusible in anaqueous alkaline medium and a second color-providing material which isnon-diffusible in said medium, said first material being capable, in thepresence of said medium, of reacting with exposed silver halide in saidlayer to form a non-diffusible product, said second material beingcapable of reacting with unexposed silver halide to form a diffusibleproduct.

6. A photographic product comprising a photosensitive element having atleast one light-sensitive silver halide layer having associatedtherewith a first color-providing material which is diffusible in anaqueous alkaline medium and a second color-providing material which isnon-diffusible in said medium, said first material being reactable withunexposed silver halide to form a non-difiY'usible product, said secondmaterial being capable of forming a difiusible product, as a function ofdeveloping exposed silver halide in said layer by contacting saidexposed silver halide with an aqueous alkaline processing medium.

7. A photographic product comprising a photosensitive element includingat least one light-sensitive silver halide layer having associatedtherewith a dye developer diffusible in an aqueous alkaline medium and acompound containing a diffusible color-providing moiety and an anchoringmoiety rendering said compound non-diffusible, said compound beingcapable of reacting with silver ions to release said diffusiblecolor-providing moiety, said compound and said dye developer beingcontained in separate layers in said element.

8. A product as defined in claim 7 wherein said layer containing saidnon-diffusible compound also includes silver-precipitating nuclei.

9. A product as defined in claim 7 wherein silverprecipitating nucleiare present in a layer contiguous with said layer of non-diffusiblecompound.

10. A product as defined in claim 7 wherein said compound upon oxidationforms an oxidation product which can autoreact intramolecularly toeffect ring-closure and to eliminate said diffusible color-providingmoiety.

11. A product as defined in claim 10 wherein said compound is of theformula:

wherein:

each of A and A represents the atoms necessary to complete an aromaticring;

D is a color-providing moiety;

Y is a substituent which completes an amide with and reduces the basiccharacter of the 3-amino substituent bonded thereto, said Y substituentfurther being a divalent radical linking said D moiety to said 3-nitrogen atom;

X and X each is hydrogen, hydroxy, amino or the substituent R, providedthat at least one of X and X must be hydroxy or amino;

R and R each represents an anchoring moiety render ing said compoundnon-difl'usible;

R is hydrogen, alkyl or substituted alkyl; and

n and 11 each is 1 or 2, provided that when R is an alkyl radical or Xor X is a secondary or tertiary amino comprising an anchoring moietyrendering said compound non-diffusible or when R X and X togethercontribute an anchoring moiety, n and n may be 1, but when saidsubstituents alone or together do not contribute an anchoring moiety atleast one of n and 11 must be 2.

12. A product as defined in claim 7 wherein said dye developer and saidcompound are of a similar color.

13. A product as defined in claim 7 wherein said dye developer and saidcompound are of complementary colors.

14. A photographic product comprising a support carrying on one sidethereof a light-sensitive silver halide emulsion having associatedtherewith a layer of difiusible dye developer and a layer containingsilver precipitating nuclei and a non-diffusible dye of the formula:

R (in) wherein:

each of R and R comprises an amide of at least 13 carbon atoms, saidamide being bonded directly to a nuclear carbon atom of the shownbenzene moiety or linked thereto through a phenylene or alkylenesubstituent; each of n and n is 1 or 2, provided that at least one ofsaid n and n is 2; and D is a monoazo, disazo or anthraquinone dyemoiety. 15. A product as defined in claim 14 including a scavenger foroxidized silver halide developing agent disposed in a layer between saidlayer containing said emulsion and said layer containing saidnon-diffusible dye. 16. A photographic product comprising a supportcarrying on one side thereof a light-sensitive silver halide emulsionhaving associated therewith a dye difiusible in an aqueous alkalinemedium and a dye which is not difiusible in said medium, said dyes beingdisposed in different layers in said element, said diffusible dye beingof the formula:

wherein A is a substituent reactable with silver ions to provide areaction product which is non-diffusible in an aqueous alkaline medium;and D is the remainder of the dye molecule; said non-diffusible dyebeing of the formula:

wherein:

complete an aromatic ring;

D is a color-providing moiety;

Y is a substituent which completes an amide with and reduces the basiccharacter of the 3-amino substituent bonded thereto, said Y substituentfurther being a divalent radical linking said D moiety to said3-nitrogen atom;

X and X each is hydrogen, hydroxy, amino or the substituent R, providedthat at least one of X and X must be hydroxy or amino;

R and R each represents an anchoring moiety rendering said compoundnon-ditfusible;

R is hydrogen, alkyl or substituted alkyl; and

n and 11 each is 1 or 2, provided that when R is an alkyl radical or Xor X is a secondary or tertiary amino comprising an anchoring moietyrendering said compound non-dilfusible or when R X and X togethercontribute an anchoring moiety, n and n may be 1, but when saidsubstituents alone or together do not contribute an anchoring moiety atleast one of n and 11 must be 2.

17. A process for forming color transfer images comprising the steps ofexposing a photosensitive element including at least one light-sensitivesilver halide layer having associated therewith a first color-providingmaterial which is normally diffusible in an aqueous alkaline processingmedium and a second color-providing material which is normallynon-ditfusible in said medium, to form a developable image;

contacting the exposed photosensitive element with an aqueous alkalineprocessing medium to develop said image and, as a function ofdevelopment, selectively immobilizing said first-named material toprovide a first imagewise distribution of mobile and difiFusiblecolor-providing material and selectively rendering said second-namedmaterial ditfusible to provide a a second imagewise distribution ofmobile and diffusible color-providing material in areas corresponding tosaid first imagewise distribution;

and transferring said two images, at least in part, by imbibition, to asuperposed stratum to impart thereto a color transfer image.

18. A process as defined in claim 17 wherein said two imagewisedistributions are formed in terms of unexposed areas of said silverhalide layer and said transfer image is a positive color image.

19. A process as defined in claim 17 wherein said color-providingmaterials are of complementary colors.

20. In a process wherein a photosensitive element including at least onelight-sensitive silver halide layer is exposed to provide exposed silverhalide areas containing a developable image and unexposed silver halideareas and said element is contacted with a processing composition todevelop said exposed silver halide areas and to form an imagewisedistribution of image-forming constituents which are transferred to astratum to impart thereto a transfer image; the improvement whichcomprises the steps of employing exposed silver halide in said layer tocontrol transfer of a first color-providing material and unexposedsilver halide to control transfer of a second color-providing material;as a function thereof forming two imagewise distributions of ditfusiblecolorproviding material for each said silver halide layer in saidelement, said two imagewise distributions being substantially identicalin terms of the point-to-point degree of exposure of said layer; andtransferring said two imagewise distributions to a superposed stratum toimpart thereto a color transfer image.

21. A process for forming images in color comprising exposing aphotosensitive element including at least one light-sensitive silverhalide layer to form a developable image; contacting said exposed layerwith an aqueous alkaline medium including a silver halide solvent and adye developer; selectively oxidizing said dye developer as a function ofdevelopment to provide an imagewise dis- 26 tribution of unreacted andunoxidized dye developer in terms of unexposed areas, and atsubstantially the same time forming an imagewise distribution of solublesilver complex in terms of unexposed silver halide; transferring saidsoluble silver complex to a layer containing a compound having acolor-providing moiety diffusible in said aqueous alkaline medium and ananchoring moiety rendering said compound non-ditfusible in said medium;reacting said compound with said complex to release said difiusiblecolor-providing moiety from said anchoring moiety, thereby providing animagewise distribution of said released diffusible moiety in terms ofunexposed areas of said silver halide layer; and transferring both ofsaid imagewise distribution of unoxidized dye developer and saidimagewise distribution of diffusible color-providing moiety, byimbibition, to a superposed stratum to impart thereto a color transferimage.

22. A process as defined in claim 21 wherein said compound is of theformula:

wherein:

each of R and R comprises an amide of at least 13 carbon atoms, saidamide being bonded directly to a nuclear carbon atom of the shownbenzene moiety or linked thereto through a phenylene or alkylenesubstituent;

each of n and n is l or 2, provided that at least one of said It and nis 2; and

D is a monoazo, disazo or anthraquinone dye moiety.

23. A process for forming negative color transfer images comprising thesteps of exposing a photosensitive element including at least onelight-sensitive silver halide emulsion to form a developable image;developing said image and as a function of development selectivelyoxidizing in terms of exposed areas of said emulsion a nondiffusiblecompound containing a diffusible dye moiety and an anchoring moietyrendering said compound nondiifusible, said compound upon oxidationforming an oxidation product which autoreacts intramolecularly to effectring-closure and to eliminate said diffusible dye, thereby forming a afirst imagewise distribution of dif fusible dye in terms of exposedareas of said emulsion; forming from unexposed silver halide in saidlayer an imagewise distribution of a soluble silver complex;transferring this imagewise distribution of soluble silver complex intoan adjacent layer containing a diifusible dye reactable with silver ionsto form a non-ditfusible reaction product; reacting said complex withsaid diffusible dye to form a non-dififusible reaction product, therebyleaving in said adjacent layer a second imagewise distribution of dye interms of exposed areas of said emulsion; and transferring both of saidimagewise diffusible dye distributions to a superposed stratum to impartthereto a negative color transfer image.

24. A process as defined in claim 23 wherein said exposed element isdeveloped by contacting it with an aqueous alkaline processingcomposition including a silver halide solvent and a silver halidedeveloping agent, and said non-difiusible compound is oxidized by aredox reaction with oxidized developing agent obtained as a function ofdeveloping exposed silver halide.

l nd-0+ j wherein:

each of A and A represents the atoms necessary to complete an aromaticring;

D is a color-providing moiety;

Y is a substituent which completes an amide with and reduces the basiccharacter of the 3-amino substituent bonded thereto, said Y substituentfurther being a divalent radical linking said D moiet to said 3-nitrogenatom;

X and X each is hydrogen, hydroxy, amino or the substituent R, providedthat at least one of X and X must be hydroxy or amino;

R and R each represents an anchoring moiety rendering said compoundnon-diffusible;

R is hydrogen, alkyl or substituted alkyl; and

n and n each is 1 or 2, provided that when R is an alkyl radical or X orX is a secondary or tertiary amino comprising an anchoring moietyrendering said compound non-diffusible or when .R X and X togethercontribute an anchoring moiety, n and 11 may be 1, but when saidsubstituents alone or together do not contribute an anchoring moiety atleast one of n and 11 must be 2.

References Cited UNITED STATES PATENTS 2,983,606 5/1961 Rogers 96-293,443,939 5/1969 Stephens 963 3,443,940 5/1969 Bloom et a1. 963

NORMAN G. TORCHIN, Primary Examiner A. T. SURO PICO, Assistant ExaminerUS. Cl. X.R.

